Although landscape features such as mountains and rivers are recognized often as limiting factors to amphibian dispersal and gene flow, a limited number of studies have investigated such patterns across Southeast Asia...Although landscape features such as mountains and rivers are recognized often as limiting factors to amphibian dispersal and gene flow, a limited number of studies have investigated such patterns across Southeast Asia. A perfect example of this is Thailand, located in one of the world's biodiversity hotspot regions. Thailand represents the corridor between mainland Asia and the Sunda Shelf, a famous and widely recognized biogeographic region, and yet there are few studies on the genetic structure among populations of amphibian species distributed across Thailand. The Southeast Asian tree frog, Chiromantis hansenae has been reported to possess a geographic range that is restricted to Thailand and, presumably, Cambodia~ Here, we investigate phylogenetic relationships among C. hansenae populations using partial sequences of the mitochondrial 16S rRNA gene and nuclear POMC gene. Our results reveal two distinct evolutionary lineages within C. hansenae populations in Thailand. The genetic divergence among populations between these two clades is considerable, and results support inter-population divergence, and high genetic differentiation (pairwise FsT = 0.97), between two localities sampled in western Thailand (TK1 and TK2), separated from each other by 40 kilometers only. The results suggest that landscape features across Thailand may have a profound impact on patterns of diversification in the country, underscoring the urgent need for fine-scale investigations of genetic structure of endemic and "widespread" species.展开更多
The Belt and Road Initiative is set to launch a new era of trade and partner- ship between China and ASEAN coun- tries, which will be extended further to Africa and Europe. China has an increas- ing influence in South...The Belt and Road Initiative is set to launch a new era of trade and partner- ship between China and ASEAN coun- tries, which will be extended further to Africa and Europe. China has an increas- ing influence in South and Southeast Asia with its support for infrastructure construction projects in local areas.展开更多
Global cooling began since 50 Ma,but a warm climate was maintained in the archipelagic tectonic system in Southeast Asia where a wealth of Cenozoic oil and gas resources was formed and preserved.From the perspective o...Global cooling began since 50 Ma,but a warm climate was maintained in the archipelagic tectonic system in Southeast Asia where a wealth of Cenozoic oil and gas resources was formed and preserved.From the perspective of Earth system,this study analyzes Cenozoic tectonic activities,climatic and environmental evolution,and petroleum enrichment in Southeast Asia,and provides the following insights:(1)Subduction of oceanic plates and the extension of overlying continental lithosphere resulted in widespread volcanic eruptions as well as the formation of rift basins and shallow marine shelves,leading to complex interactions between deep tectonic processes and Earth’s surface including mountains,basins,and seas.(2)Microcontinental accretion and prolonged stay in equatorial low-latitude regions have changed trade winds into monsoons,altered ocean current pathways and flow rates,and profoundly affected rainfall and climate.(3)The archipelagic tectonic system,coupled with a hot and rainy climate,fostered tropical rainforests,mangroves,and phytoplankton,providing abundant organic matter and promoting the development of petroleum resources.(4)Combinations of rift basin development and marine transgression and regression led to an effective superposition of source-reservoir-seal combinations from multiplepetroleum systems.Rapid deep burial of organic matter and high geothermal gradients facilitated the generation and large-scale accumulation of oil and gas.(5)Multi-spherical(such as atmosphere,biosphere,hydrosphere and lithosphere)interactions on the Earth,which resulted from the convergence of multiple tectonic plates,are believed as the primary driver for exceptional enrichments of Cenozoic oil and gas resources in Southeast Asia.These understandings are significant for developing theories of oil and gas enrichment under the guidance of Earth System Science.In order to continue making significant oil and gas exploration discoveries in the deep-layers,deep-waters,and unconventional oil and gas fields of Southeast Asia,attention should be paid to the oil and gas resource effects of the collision between Australia and Sunda blocks and the high-temperature and high-rainfall climate environment,and efforts should be made to develop economic development and CO_(2)sequestration technologies for offshore CO_(2)-rich gas fields.展开更多
基金supported by Kasetsart University research grant (No. 28.56) from the Kasetsart University Research and Development Institute (KURDI)ScRF grant (No. S14/2555) from Faculty of Science, Kasetsart University+1 种基金Support for Cameron D. SILER to develop new international collaborations with the Amphibians and Reptiles Ecology LaboratoryKasetsart University was supported by international travel grants provided by the Department of Biology and College of Arts and Sciences at the University of Oklahoma
文摘Although landscape features such as mountains and rivers are recognized often as limiting factors to amphibian dispersal and gene flow, a limited number of studies have investigated such patterns across Southeast Asia. A perfect example of this is Thailand, located in one of the world's biodiversity hotspot regions. Thailand represents the corridor between mainland Asia and the Sunda Shelf, a famous and widely recognized biogeographic region, and yet there are few studies on the genetic structure among populations of amphibian species distributed across Thailand. The Southeast Asian tree frog, Chiromantis hansenae has been reported to possess a geographic range that is restricted to Thailand and, presumably, Cambodia~ Here, we investigate phylogenetic relationships among C. hansenae populations using partial sequences of the mitochondrial 16S rRNA gene and nuclear POMC gene. Our results reveal two distinct evolutionary lineages within C. hansenae populations in Thailand. The genetic divergence among populations between these two clades is considerable, and results support inter-population divergence, and high genetic differentiation (pairwise FsT = 0.97), between two localities sampled in western Thailand (TK1 and TK2), separated from each other by 40 kilometers only. The results suggest that landscape features across Thailand may have a profound impact on patterns of diversification in the country, underscoring the urgent need for fine-scale investigations of genetic structure of endemic and "widespread" species.
文摘The Belt and Road Initiative is set to launch a new era of trade and partner- ship between China and ASEAN coun- tries, which will be extended further to Africa and Europe. China has an increas- ing influence in South and Southeast Asia with its support for infrastructure construction projects in local areas.
基金supported by the National Natural Science Foundation of China(Grant Nos.42288201,92255303,42202162)。
文摘Global cooling began since 50 Ma,but a warm climate was maintained in the archipelagic tectonic system in Southeast Asia where a wealth of Cenozoic oil and gas resources was formed and preserved.From the perspective of Earth system,this study analyzes Cenozoic tectonic activities,climatic and environmental evolution,and petroleum enrichment in Southeast Asia,and provides the following insights:(1)Subduction of oceanic plates and the extension of overlying continental lithosphere resulted in widespread volcanic eruptions as well as the formation of rift basins and shallow marine shelves,leading to complex interactions between deep tectonic processes and Earth’s surface including mountains,basins,and seas.(2)Microcontinental accretion and prolonged stay in equatorial low-latitude regions have changed trade winds into monsoons,altered ocean current pathways and flow rates,and profoundly affected rainfall and climate.(3)The archipelagic tectonic system,coupled with a hot and rainy climate,fostered tropical rainforests,mangroves,and phytoplankton,providing abundant organic matter and promoting the development of petroleum resources.(4)Combinations of rift basin development and marine transgression and regression led to an effective superposition of source-reservoir-seal combinations from multiplepetroleum systems.Rapid deep burial of organic matter and high geothermal gradients facilitated the generation and large-scale accumulation of oil and gas.(5)Multi-spherical(such as atmosphere,biosphere,hydrosphere and lithosphere)interactions on the Earth,which resulted from the convergence of multiple tectonic plates,are believed as the primary driver for exceptional enrichments of Cenozoic oil and gas resources in Southeast Asia.These understandings are significant for developing theories of oil and gas enrichment under the guidance of Earth System Science.In order to continue making significant oil and gas exploration discoveries in the deep-layers,deep-waters,and unconventional oil and gas fields of Southeast Asia,attention should be paid to the oil and gas resource effects of the collision between Australia and Sunda blocks and the high-temperature and high-rainfall climate environment,and efforts should be made to develop economic development and CO_(2)sequestration technologies for offshore CO_(2)-rich gas fields.